A control system that controls a plurality of object apparatuses (energy management system: EMS) has lately attracted attention (for example, refer to Patent Literature 1). This type of control system includes a control apparatus that controls a plurality of apparatuses, provided therein.
Examples of the control apparatus include a home energy management system (HEMS) provided in a dwelling, a building energy management system (BEMS) provided in a building, a factory energy management system (FEMS) provided in a factory, and a store energy management system (SEMS) provided in a store.
Examples of the plurality of object apparatuses include a decentralized power source, a power storage apparatus, a heat storage apparatus, and a load. The decentralized power source is an apparatus that generates power using natural energy, such as sunlight, wind force, or geotherm. Alternatively, the decentralized power source is an apparatus that generates power using fuel gas, as a fuel cell such as a solid oxide fuel cell (SOFC). The power storage apparatus is an apparatus that stores power as a secondary battery. The heat storage apparatus is an apparatus that converts power into heat and stores the heat as a water heater. Examples of the load include a refrigerator, a lighting equipment, an air conditioning equipment, and a television.
In order to achieve that appropriate communication is performed between the control apparatus and the object apparatuses, standards according to the communication between the control apparatus and the object apparatuses (for example, ECHONET Lite) have been developed. Accordingly, the control apparatus can transmit various control commands to the object apparatuses.
However, when the control apparatus specifies a value which the object apparatuses are not capable of dealing with, by the control commands, errors occur on the side of the object apparatuses. The control apparatus needs to grasp a range of values relating to ability of each of the object apparatuses in advance.
In the above background, it is thought that a message in which the control apparatus requests the range of the values relating to the ability of each of the object apparatuses from the object apparatuses, is defined anew with the standards. Defining this type of message anew is unfavorable in terms of backward capability.